Evaluation of vaccine delivery systems for inducing long-lived antibody responses to Dermanyssus gallinae antigen in laying hens.

Evaluation of vaccine delivery systems for inducing long-lived antibody responses to Dermanyssus gallinae antigen in laying hens. Avian Pathol. 2019 Apr 29;:1-44 Authors: Price DRG, Küster T, Øines Ø, Margaret Oliver E, Bartley K, Nunn F, Barbero JFL, Pritchard J, Karp-Tatham E, Hauge H, Blake DP, Tomley FM, Nisbet AJ Abstract Dermanyssus gallinae, the poultry red mite, is a global threat to the commercial egg-laying industry. Control of D. gallinae is difficult, with only a limited number of effective pesticides and non-chemical treatments available. Here we characterise the candidate vaccine antigen D. gallinae cathepsin D-1 (Dg-CatD-1) and demonstrate that purified refolded recombinant Dg-Cat-D1 (rDg-CatD-1) is an active aspartyl proteinase which digests haemoglobin with a pH optimum of pH 4. Soluble protein extracts from D. gallinae also have haemoglobinase activity, with a pH optimum comparable to the recombinant protein and both proteinase activities were inhibited by the aspartyl proteinase inhibitor Pepstatin A. Enzyme activity and the ubiquitous localization of Dg-CatD-1 protein in sections of adult female mites is consistent with Dg-CatD-1 being a lysosomal proteinase. Using Dg-CatD-1 as a model vaccine antigen, we compared vaccine delivery methods in laying hens via vaccination with: i) purified rDg-CatD-1 with Montanide™ ISA 71 VG adjuvant; ii) recombinant DNA vaccines for expression of rDg-CatD-1 and iii) transgenic...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research